- - AGRICULTURE CORE CURRICULUM - -

(CLF6000) Advanced Core Cluster: ORNAMENTAL HORTICULTURE

 (CLF6250) Unit Title: SEXUAL AND ASEXUAL PROPAGATION

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 (CLF6254) Topic: REPRODUCTION BY SPORES      Time              Year(s) 
                                                 1 hour              3 / 4 
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         Topic Objectives: Upon completion of this lesson, the student
                            will be able to:

         Learning Outcome #:

           (D-2) - Discuss how some plants (e.g., ferns and fungi)
                     reproduce sexually by means other than seeds.

         Special Materials and Equipment: Fern fronds and hand lens

         References: Hartmann, H. T., & Kester, D. (1983). PLANT 
                       PROPAGATION: PRINCIPLES AND PRACTICES 
                       (4th ed.). Englewood Cliffs, NJ: Prentice-Hall.
                     Hoshizaki, Barbara. (1975). FERN GROWERS MANUAL.
                       New York: Knopf.

         Evaluation: By quiz or test

TOPIC PRESENTATION: REPRODUCTION BY SPORES

A. The propagation body of flowerless plants (for example, ferns) are 
   spores.

B. Ferns have two life cycles.

   1. Sporophyte generation - these are mature plants as seen in pots and 
       landscapes.

   2. Gametophyte generation - the reproduction stage.

       a. This starts with the mature plant's spores landing on a moist 
           place with sufficient light to germinate.

       b. After several days the spore sends out a cell (a rhizoid) which 
           secures the cell in place.

       c. In about three months a heart-shaped tissue called a gametophyte
           is formed.

       d. The gametophyte contains eggs and sperm which fertilize each 
           other (a film of water must be present).

       e. This fertilization marks the start of the sporophyte.

       f. About five months to a year after the spores have been planted,
           a small fern is developed.

       g. Most ferns take about two years to complete the full life cycle,
           that is, from spore to spore-bearing fronds.

C. Spore Production

   1. Growing ferns from spores takes patience and time.

   2. Most trade ferns take about six to ten months from sowing to 
       planting into two-inch pots.

   3. Collecting spores

       a. Spore cases (sporangia) are usually on the underside of the 
           frond.

       b. Sporangia turn from green to light brown as they ripen.

       c. Fronds with sporangia can be placed in an envelope for maximum
           collection of the spores.


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         ACTIVITY: 
 
         1.  Bring in fronds of mature ferns and look at the 
              sporangia with a hand lens or dissecting microscope.

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1/6/91 MT/clh

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